diff --git a/artifacts/cra-app/src/components/layout/sidebar.tsx b/artifacts/cra-app/src/components/layout/sidebar.tsx
index f9e3db0..28e3824 100644
--- a/artifacts/cra-app/src/components/layout/sidebar.tsx
+++ b/artifacts/cra-app/src/components/layout/sidebar.tsx
@@ -1,14 +1,14 @@
 import { useRef, useState } from "react";
 import { Link, useLocation } from "wouter";
-import { Download, FolderKanban, LayoutDashboard, Settings, Upload, Clock } from "lucide-react";
+import { Download, FolderKanban, LayoutDashboard, Lock, LockOpen, Settings, Upload, Clock } from "lucide-react";
 import { cn } from "@/lib/utils";
 import { QuickEntryButton } from "@/components/quick-entry";
 import { Button } from "@/components/ui/button";
 import { Dialog, DialogContent, DialogFooter, DialogHeader, DialogTitle } from "@/components/ui/dialog";
 import { Input } from "@/components/ui/input";
 import { Label } from "@/components/ui/label";
-import { getAppInfo, saveAppInfo, type AppInfo } from "@/lib/app-info";
 import { useToast } from "@/hooks/use-toast";
+import { isAdminUnlocked, lockAdmin, unlockAdmin, useAdminUnlocked } from "@/lib/admin-mode";
 
 const navItems = [
   {
@@ -31,22 +31,38 @@ const navItems = [
 export function AppSidebar() {
   const [location] = useLocation();
   const [isAdminOpen, setIsAdminOpen] = useState(false);
-  const [info, setInfo] = useState<AppInfo>(() => getAppInfo());
+  const [adminCode, setAdminCode] = useState("");
   const [isImporting, setIsImporting] = useState(false);
+  const adminUnlocked = useAdminUnlocked();
   const fileInputRef = useRef<HTMLInputElement>(null);
   const { toast } = useToast();
 
   const handleOpenAdmin = () => {
-    setInfo(getAppInfo());
+    setAdminCode("");
     setIsAdminOpen(true);
   };
 
-  const handleSaveInfo = () => {
-    saveAppInfo(info);
-    toast({ title: "Informations mises à jour" });
+  const handleUnlock = () => {
+    if (unlockAdmin(adminCode)) {
+      setAdminCode("");
+      toast({ title: "Saisie déverrouillée" });
+      return;
+    }
+
+    toast({ title: "Code admin incorrect", variant: "destructive" });
+  };
+
+  const handleLock = () => {
+    lockAdmin();
+    toast({ title: "Saisie verrouillée" });
   };
 
   const handleExport = async () => {
+    if (!isAdminUnlocked()) {
+      toast({ title: "Déverrouillez d'abord le mode admin", variant: "destructive" });
+      return;
+    }
+
     const response = await fetch("/api/admin/export");
     if (!response.ok) {
       toast({ title: "Export impossible", variant: "destructive" });
@@ -64,6 +80,10 @@ export function AppSidebar() {
 
   const handleImport = async (file: File | undefined) => {
     if (!file) return;
+    if (!isAdminUnlocked()) {
+      toast({ title: "Déverrouillez d'abord le mode admin", variant: "destructive" });
+      return;
+    }
     if (!confirm("Importer ce fichier remplacera toutes les données actuelles. Continuer ?")) return;
 
     setIsImporting(true);
@@ -123,21 +143,30 @@ export function AppSidebar() {
         <button
           type="button"
           onClick={handleOpenAdmin}
-          className="flex w-full items-center gap-3 rounded-md px-3 py-2.5 text-sm font-medium transition-colors cursor-pointer text-sidebar-foreground/70 hover:bg-sidebar-accent/50 hover:text-sidebar-foreground"
+          className={cn(
+            "flex w-full items-center gap-3 rounded-md px-3 py-2.5 text-sm font-medium transition-colors cursor-pointer",
+            adminUnlocked
+              ? "bg-green-50 text-green-700 hover:bg-green-100"
+              : "text-sidebar-foreground/70 hover:bg-sidebar-accent/50 hover:text-sidebar-foreground"
+          )}
         >
-          <Settings className="h-4 w-4 text-muted-foreground" />
-          Admin
+          {adminUnlocked ? (
+            <LockOpen className="h-4 w-4 text-green-600" />
+          ) : (
+            <Settings className="h-4 w-4 text-muted-foreground" />
+          )}
+          {adminUnlocked ? "Admin actif" : "Admin"}
         </button>
       </nav>
 
       <div className="p-4 border-t border-sidebar-border">
         <div className="flex items-center gap-3 px-3 py-2">
           <div className="h-8 w-8 rounded-full bg-primary/10 flex items-center justify-center text-primary font-bold text-xs">
-            {info.userInitials}
+            JD
           </div>
           <div className="flex flex-col">
-            <span className="text-sm font-medium">{info.userName}</span>
-            <span className="text-xs text-muted-foreground">{info.userRole}</span>
+            <span className="text-sm font-medium">Jean Dupont</span>
+            <span className="text-xs text-muted-foreground">Consultant</span>
           </div>
         </div>
       </div>
@@ -150,32 +179,47 @@ export function AppSidebar() {
 
           <div className="space-y-5">
             <div className="space-y-3">
-              <h3 className="text-sm font-semibold">Informations affichées</h3>
-              <div className="grid grid-cols-2 gap-3">
-                <div className="space-y-1.5">
-                  <Label>Nom</Label>
-                  <Input value={info.userName} onChange={(e) => setInfo({ ...info, userName: e.target.value })} />
+              <h3 className="text-sm font-semibold">Protection de la saisie</h3>
+              {adminUnlocked ? (
+                <div className="rounded-md border border-green-200 bg-green-50 p-3 text-sm text-green-800">
+                  La saisie est déverrouillée. Les cellules CRA et la saisie rapide sont modifiables.
                 </div>
-                <div className="space-y-1.5">
-                  <Label>Rôle</Label>
-                  <Input value={info.userRole} onChange={(e) => setInfo({ ...info, userRole: e.target.value })} />
+              ) : (
+                <div className="rounded-md border bg-muted/30 p-3 text-sm text-muted-foreground">
+                  La saisie est verrouillée. Déverrouillez le mode admin pour modifier les heures.
                 </div>
-                <div className="space-y-1.5">
-                  <Label>Initiales</Label>
-                  <Input value={info.userInitials} onChange={(e) => setInfo({ ...info, userInitials: e.target.value })} />
+              )}
+              <div className="flex gap-2">
+                <div className="flex-1 space-y-1.5">
+                  <Label>Code admin</Label>
+                  <Input
+                    type="password"
+                    value={adminCode}
+                    onChange={(e) => setAdminCode(e.target.value)}
+                    onKeyDown={(e) => {
+                      if (e.key === "Enter") handleUnlock();
+                    }}
+                    placeholder="Code admin"
+                    disabled={adminUnlocked}
+                  />
                 </div>
-                <div className="space-y-1.5">
-                  <Label>Date de déploiement</Label>
-                  <Input value={info.deployDate} onChange={(e) => setInfo({ ...info, deployDate: e.target.value })} />
-                </div>
-                <div className="space-y-1.5 col-span-2">
-                  <Label>Lien du repo</Label>
-                  <Input value={info.repoUrl} onChange={(e) => setInfo({ ...info, repoUrl: e.target.value })} />
+                <div className="flex items-end">
+                  {adminUnlocked ? (
+                    <Button variant="outline" onClick={handleLock} className="gap-2">
+                      <Lock className="h-4 w-4" />
+                      Verrouiller
+                    </Button>
+                  ) : (
+                    <Button onClick={handleUnlock} className="gap-2">
+                      <LockOpen className="h-4 w-4" />
+                      Déverrouiller
+                    </Button>
+                  )}
                 </div>
               </div>
-              <Button size="sm" onClick={handleSaveInfo}>
-                Enregistrer les informations
-              </Button>
+              <p className="text-xs text-muted-foreground">
+                Code par défaut : 1234
+              </p>
             </div>
 
             <div className="space-y-3 border-t pt-4">
@@ -189,7 +233,7 @@ export function AppSidebar() {
                   variant="outline"
                   size="sm"
                   onClick={() => fileInputRef.current?.click()}
-                  disabled={isImporting}
+                  disabled={isImporting || !adminUnlocked}
                   className="gap-2"
                 >
                   <Upload className="h-4 w-4" />
diff --git a/artifacts/cra-app/src/components/quick-entry.tsx b/artifacts/cra-app/src/components/quick-entry.tsx
index 5b5d6e1..3f2707a 100644
--- a/artifacts/cra-app/src/components/quick-entry.tsx
+++ b/artifacts/cra-app/src/components/quick-entry.tsx
@@ -27,24 +27,39 @@ import {
 } from "@/components/ui/select";
 import { Textarea } from "@/components/ui/textarea";
 import { useToast } from "@/hooks/use-toast";
-import { Zap, Clock, Check } from "lucide-react";
+import { Zap, Clock, Check, Lock } from "lucide-react";
 import { format } from "date-fns";
 import { fr } from "date-fns/locale";
+import { useAdminUnlocked } from "@/lib/admin-mode";
+import { cn } from "@/lib/utils";
 
-const HOUR_OPTIONS = [0.5, 1, 2, 3, 4, 5, 6, 7, 7.7];
+const HOUR_OPTIONS = [0.5, 1, 2, 3, 4, 5, 6, 7, 8];
 const COLLABORATOR = "PHAM Sylvain";
 
 export function QuickEntryButton() {
   const [open, setOpen] = useState(false);
+  const adminUnlocked = useAdminUnlocked();
+  const { toast } = useToast();
 
   return (
     <>
       <button
-        onClick={() => setOpen(true)}
-        className="flex items-center gap-3 rounded-md px-3 py-2.5 text-sm font-medium transition-colors cursor-pointer w-full bg-primary/10 text-primary hover:bg-primary/20"
+        onClick={() => {
+          if (!adminUnlocked) {
+            toast({ title: "Saisie verrouillée", description: "Déverrouillez le mode admin pour saisir des heures." });
+            return;
+          }
+          setOpen(true);
+        }}
+        className={cn(
+          "flex items-center gap-3 rounded-md px-3 py-2.5 text-sm font-medium transition-colors cursor-pointer w-full",
+          adminUnlocked
+            ? "bg-primary/10 text-primary hover:bg-primary/20"
+            : "text-sidebar-foreground/50 bg-muted/40"
+        )}
         data-testid="button-quick-entry"
       >
-        <Zap className="h-4 w-4" />
+        {adminUnlocked ? <Zap className="h-4 w-4" /> : <Lock className="h-4 w-4" />}
         Saisie rapide
       </button>
       <QuickEntryDialog open={open} onOpenChange={setOpen} />
diff --git a/artifacts/cra-app/src/lib/admin-mode.ts b/artifacts/cra-app/src/lib/admin-mode.ts
new file mode 100644
index 0000000..fdcfef0
--- /dev/null
+++ b/artifacts/cra-app/src/lib/admin-mode.ts
@@ -0,0 +1,34 @@
+import { useEffect, useState } from "react";
+
+export const ADMIN_MODE_EVENT = "cra-admin-mode-updated";
+const ADMIN_UNLOCKED_KEY = "cra-admin-unlocked";
+const ADMIN_CODE = "1234";
+
+export function isAdminUnlocked() {
+  if (typeof window === "undefined") return false;
+  return window.sessionStorage.getItem(ADMIN_UNLOCKED_KEY) === "true";
+}
+
+export function unlockAdmin(code: string) {
+  if (code !== ADMIN_CODE) return false;
+  window.sessionStorage.setItem(ADMIN_UNLOCKED_KEY, "true");
+  window.dispatchEvent(new Event(ADMIN_MODE_EVENT));
+  return true;
+}
+
+export function lockAdmin() {
+  window.sessionStorage.removeItem(ADMIN_UNLOCKED_KEY);
+  window.dispatchEvent(new Event(ADMIN_MODE_EVENT));
+}
+
+export function useAdminUnlocked() {
+  const [unlocked, setUnlocked] = useState(() => isAdminUnlocked());
+
+  useEffect(() => {
+    const handleUpdate = () => setUnlocked(isAdminUnlocked());
+    window.addEventListener(ADMIN_MODE_EVENT, handleUpdate);
+    return () => window.removeEventListener(ADMIN_MODE_EVENT, handleUpdate);
+  }, []);
+
+  return unlocked;
+}
\ No newline at end of file
diff --git a/artifacts/cra-app/src/pages/timesheet-detail.tsx b/artifacts/cra-app/src/pages/timesheet-detail.tsx
index b4774e6..0e74d73 100644
--- a/artifacts/cra-app/src/pages/timesheet-detail.tsx
+++ b/artifacts/cra-app/src/pages/timesheet-detail.tsx
@@ -18,7 +18,8 @@ import {
   Trash2, 
   CheckCircle,
   AlertCircle,
-  MessageSquare
+  MessageSquare,
+  Lock
 } from "lucide-react";
 import { Button } from "@/components/ui/button";
 import { Badge } from "@/components/ui/badge";
@@ -33,6 +34,7 @@ import { Dialog, DialogContent, DialogHeader, DialogTitle, DialogFooter } from "
 import { Popover, PopoverContent, PopoverTrigger } from "@/components/ui/popover";
 import { useToast } from "@/hooks/use-toast";
 import { formatMonthYear, STATUS_LABELS, STATUS_COLORS, cn } from "@/lib/utils";
+import { useAdminUnlocked } from "@/lib/admin-mode";
 import { getDaysInMonth, isWeekend, format } from "date-fns";
 import { fr } from "date-fns/locale";
 
@@ -49,6 +51,7 @@ export default function TimesheetDetailPage() {
   
   const { toast } = useToast();
   const queryClient = useQueryClient();
+  const adminUnlocked = useAdminUnlocked();
   
   const { data: timesheet, isLoading } = useGetTimesheet(
     timesheetId,
@@ -108,9 +111,9 @@ export default function TimesheetDetailPage() {
     return { 
       days: daysCount, 
       daysArray: arr,
-      isEditable: timesheet.status === "draft"
+      isEditable: timesheet.status === "draft" && adminUnlocked
     };
-  }, [timesheet]);
+  }, [timesheet, adminUnlocked]);
 
   const HOUR_OPTIONS = [0, 0.5, 1, 2, 3, 4, 5, 6, 7, 8];
   const [saveStatus, setSaveStatus] = useState<"idle" | "saving" | "saved">("idle");
@@ -346,6 +349,12 @@ export default function TimesheetDetailPage() {
               </Button>
             </>
           )}
+          {timesheet.status === "draft" && !adminUnlocked && (
+            <Badge variant="outline" className="bg-amber-50 text-amber-700 border-amber-200 px-3 py-1.5 text-sm gap-1">
+              <Lock className="h-4 w-4" />
+              Saisie verrouillée
+            </Badge>
+          )}
           {timesheet.status === "submitted" && (
             <Badge className="bg-blue-100 text-blue-800 hover:bg-blue-100 border-none px-3 py-1.5 text-sm gap-1">
               <AlertCircle className="h-4 w-4" />
diff --git a/attached_assets/image_1776768428924.png b/attached_assets/image_1776768428924.png
new file mode 100644
index 0000000..9ed614c
Binary files /dev/null and b/attached_assets/image_1776768428924.png differ
diff --git a/replit.md b/replit.md
index e4b1a45..7e8e7ac 100644
--- a/replit.md
+++ b/replit.md
@@ -26,7 +26,7 @@ A French timesheet management application (CRA - Compte Rendu d'Activité) built
 - **CRA Grid**: Interactive calendar grid where rows = projects, columns = days of month. Click cells to open popover with hour options [0, 0.5, 1, 2, 3, 4, 5, 6, 7, 8]. Includes optional description per cell (amber dot indicator). Auto-save with debounce. Weekend distinction, row/column totals
 - **Project Management**: CRUD for projects with code, name, client, category
 - **Timesheet Workflow**: Draft → Submitted → Validated status flow
-- **Inline Administration**: Sidebar Admin dialog to edit displayed app/user metadata and export/import project, CRA, line, and time-entry data as JSON
+- **Inline Administration**: Sidebar Admin dialog to lock/unlock time entry editing and export/import project, CRA, line, and time-entry data as JSON
 
 ## Database Schema